COUNTY · NH

Hillsborough County, New Hampshire

Hillsborough County is a county in New Hampshire with FIPS code 33011 and an estimated population of 427,354 (Census 2023), 1st largest of 10 in the state.

County facts

Name: Hillsborough County
State: New Hampshire
Type: county
FIPS code: 33011
State FIPS: 33
Population (2023): 427,354
Change since 2020: +1.1%
State rank: 1 of 10

Population is the Census Bureau’s Vintage 2023 estimate.

Major cities in Hillsborough County

Manchester

Other counties in New Hampshire

Rockingham County Merrimack County Strafford County Grafton County Cheshire County Belknap County Carroll County Sullivan County All 10

Questions

What is the FIPS code for Hillsborough County?

Hillsborough County, New Hampshire has the five-digit FIPS code 33011: 33 for the state and 011 for the county.

What state is Hillsborough County in?

Hillsborough County is in New Hampshire.

How do I know if an address is in this county?

Use the address lookup. ZIP codes and city names can cross county lines, so an address is the reliable check.

Sources: U.S. Census Bureau geographic reference files; Census Bureau Population Estimates, Vintage 2023. Last reviewed 2026-10-27.